function swap() {
	
	var state = (document.getElementById('quell_id').value);
	
	if (state == 1) {
		document.getElementById('www').style.display = 'block';
		document.getElementById('print').style.display = 'none';
	}
	else {
		document.getElementById('www').style.display = 'none';
		document.getElementById('print').style.display = 'block';
	}

}

function checkInput() {
	var textfeld = document.getElementById('textfeld').value;
	if (trim(textfeld) != "") {
		return true;
	}
	else {
		return false;
	}
}



function trim(s) {
  while (s.substring(0,1) == ' ') {
    s = s.substring(1,s.length);
  }
  while (s.substring(s.length-1,s.length) == ' ') {
    s = s.substring(0,s.length-1);
  }
  return s;
}